- Email: [email protected]
Planning agricultural wastewater reuse in southern Italy: The case of Apulia Region
Desalination 218 (2008) 164–169
Planning agricultural wastewater reuse in southern Italy: The case of Apulia Region A. Lopez*, M. Vurro Consiglio Nazionale delle Ricerche, Istituto di Ricerca Sulle Acque, Via F. De Blasio 5, 70123 Bari, Italy Tel. +39 (080) 5820511; Fax +39 (080) 5313365; email: [email protected], [email protected]
Received 1 February 2006; accepted 30 August 2006
Abstract The future of southern Italian regions lays mainly on conservation and recovery of their peculiar environment (i.e., pleasant climate, beautiful nature and historic heritage). Presently, most of such regions have to face major problems related to water shortage for agriculture and, in some cases, even for drinking purposes. In these regions water shortage is a growing problem and wastewater reclamation and reuse, a key options for their sustainable development, has not yet been implemented at large scale. In these regions, the interest for wastewater reuse is particularly addressed to agricultural and landscape irrigation with the aim of both enhancing the local economy, mostly based on agriculture, and saving good quality water resources for drinking purposes. Referring to the Apulia region, it has many analogies with other areas affected by chronic water scarcity, i.e: the rapid development of local economy, the changes in traditional agriculture practices and land use, the groundwater over-exploitation with consequent sea water intrusion, the climate changes. The mix of all these factors, although with a different weight, has been the main cause of the frequent water shortage problems recorded in the region. Although over the last decades these problems have been partially mitigated by the construction of water transport infrastructures and reservoirs, they are still far to be definitely solved. Because of this, finally, regional authorities have defined a water resources protection and management master plan in which the reuse of treated wastewater, not only in agriculture, plays a relevant role [1]. This paper outlines the local environmental conditions and the rationale supporting such a choice. Keywords: Agricultural wastewater reuse; Wastewater treatment; Water resources management
*Corresponding author.
Presented at AQUAREC 2006 — Integrated Concepts for Reuse of Upgraded Wastewater, Barcelona, 1–3 February 2006 0011-9164/08/$– See front matter © 2008 Published by Elsevier B.V. doi:10.1016/j.desal.2006.08.027
A. Lopez, M. Vurro / Desalination 218 (2008) 164–169
1. Introduction In Italy, an overall annual water inflow around 155 billions m3 yields only 52 billions m3 of resources actually utilizable. Because of the geographically uneven rainfalls distribution, in southern regions (e.g., Apulia, Sicily and Sardinia) such figures drastically decrease as rainfalls result much lower than the national average (980 mm/y) [2]. Furthermore, in such regions, only part (15– 20%) of these scarce water resources is actually available mainly because of their out of date water distribution systems. At national level, Apulia, a southern-eastern region extended for about 20,000 km2 with 800 km of coasts and 4,500,000 inhabitants, owns the smallest amount (136 m3/capita/y) of potentially available water resources [2]. Nevertheless, the economy of the region, mainly based on two water demanding activities, agriculture and tourism, is ranked as one of the best in the south. This is possible thanks to the Apulian water agency (AQP) that imports water from bordering regions such as Campania, Lucania and Molise. AQP manages the largest European aqueduct, a complex multi-purposes and multi-reservoirs system with 19,635 km of distribution networks. It serves 4,623,349 inhabitants and distributes, net of leakages, 309,416,113 m3 of drinking water [3]. As for the agricultural sector, although it is served by large irrigation-water distribution consortia, a negative gap of about 700 Mm3 exists. To fill this gap, it has been estimated that regional farmers have drilled, more or less legally, about 140,000 wells whose extensive exploitation has caused the progressive salinization and depletion of relevant portions of the local aquifers. In order to manage such a situation, regional authorities in addition to drastically restrict water wells drilling have also planned a strategic reuse, in agriculture as well as in industry, of treated municipal wastewater (MWW) [1]. Referring only to the agricultural sector, this paper is aimed at qualitatively describing some features of the Apulia region related to its water
165
resources scarcity, the criteria that have driven the selection of the MWW treatment plants whose effluents have been planned to be reused in agriculture and some information concerning the treatment-scheme of such plants. 2. Planning agricultural wastewater reuse in Apulia 2.1. Environmental drivers As shown in Fig. 1, Apulia is the Italian region with the lowest rainfall average value (i.e. about 660 mm) [2]. Furthermore because of its orography and its hydro- geological subsoil features, its average runoff coefficient value (0.23) is also the lowest. This value has been calculated, by a model designed for evaluating groundwater recharge through a soil-water balance, taking into account inflows (rainfall, irrigation) and outflows (plant evapotranspiration, surface run-off) [4].
<500 501-750 751-1000 1001-1500 1501-2000 2001-2500 >2500
APULIA
Fig. 1. Rainfalls distribution in Italy: average values (mm) in the period 1950–2000.
166
A. Lopez, M. Vurro / Desalination 218 (2008) 164–169
In spite of the scarce regional rainfalls, Fig. 2 shows that most (78.8%) of the Apulian land is used for agricultural purposes (i.e., 15,239 km2 over a total area of 19,332 km2). In must be noted, however, that only 23.8% (i.e., 3,653 km2) of the cultivated area is irrigated. Notwithstanding such a small portion of irrigated land, in order to satisfy the agricultural water demand, as shown in Fig. 3, in the region, relevant amounts of water are withdrawn from local aquifers [4].
Of course, because of such a groundwater overexploitation, particularly in coastal areas, a sharp salinity increase, with peaks such high as 20,000 µS/cm, has taken place due to sea water intrusion phenomena (Fig. 4) [5]. 2.2. Legislative framework From the legislative standpoint the above mentioned regional master plan is based mainly on two national laws, i.e. the D.Lgs n.152/99 and n. 185/03 [6,7]. The latter law, for the fist time, clearly fixed the qualitative standards for WW agricultural reuse (Table 1) giving to each region, if justified, the possibility to modify only some parameters. As for D.Lgs n.152/99, it combines the European Directives 91/271/EEC (on the treatment of urban wastewater) and 91/676/EEC (on water resources protection from the pollution caused by nitrates from agricultural sources). Moreover, this law provides general provisions for protecting water resources from whatever pollution. Among such provisions, one imposes that wastewater discharge into subsoil, a rather frequent practice in Apulia, has to be stopped as soon as possible, in-
Fig. 2. Land use in Apulia.
0 0000008 4 1 2 8 9 5 4 4 4 3 3 2 3 )0 m 0 04 01 02 08 05 9 52 m2 4 34 33 ( N O I T A 00005 0 G 03 6 9 2 I 01 0 1 1 1 2 2 R 05 R1 -I 03 06 09 02 0 -0 L 00 A U 01511112 N N A
KEY
Fig. 3. Groundwater withdrawals (mm/y) for irrigation purposes in Apulia.
Fig. 4. Electrical conductivity (µS/cm) of Apulian aquifers.
A. Lopez, M. Vurro / Desalination 218 (2008) 164–169
167
Table 1 Main quality parameters fixed by the Italian law (D.Lgs n. 185/03) for agricultural reuse of municipal wastewater
Parameter
Value
pH Coarse solids, mg/L TSS, mg/L COD, mg/L BOD5, mg/L Boron, mg/L Chlorides, mg/L Sulphates, mg/L Electrical conductivity, µS/cm Total phosphorus, mg/L Total nitrogen, mg/L Grease and oil, mg/L Aldehydes, mg/L Surfactants Chlorinated pesticides Escherichia coli, CFU/100 ml Salmonella, CFU/100 ml Sodium adsorption ratio
6–9.5 absent 10 100* (50) 20* (10) 1.0* (2.0) 250* (500) 500 3,000 10 35 10 0.5 0.5 0.0001 10 absent 10
(*) Values modified by the Apulia region with those in parenthesis.
dicating the reuse of treated wastewater as a feasible alternative. Such provisions together with the persistent water resources scarcity have finally convinced the regional Government to insert the reuse of municipal wastewater in the official planning of the management of regional water resources [1]. 2.3. Wastewater availability and technical issues In the whole region there are 215 wastewater treatments plants: 173 managed by AQP, 29 by single municipalities, 2 directly by the Apulia region and 11 not yet in operation. The plants managed by AQP (Fig. 5) have a total designed capacity of about 250 Mm3/y of treated WW [8,9]. The regional master plan that defines the whole strategy for the protection and the management of local water resources also provides the details
Fig. 5. Distribution of the municipal wastewater treatment plants managed by the Apulian Water Agency (AQP).
(i.e., MWWTPs exploitable, available WW volumes, costs, timing, etc.) for implementing the programmed wastewater reuse [1]. In particular, it takes into account that from the technological, infrastructural, logistic and economic standpoints, not all the AQP plants can be involved in the wastewater reuse plan. In fact, some of them have a small capacity, or are very far from agricultural districts, or are equipped only with preliminary or primary treatment sections, or cannot be connected to the necessary infrastructural-works (e.g., wastewater distribution pipelines, etc.). All such plants features have been inserted in a GIS tool that has been used for identifying, in a first planning-step, those plants (Table 2) potentially utilizable, in relatively short time, for reusing their treated wastewater (it must be pointed out that the recoverable volumes reported in Table 2 are only those planned to be reused in the reference area). In Table 2 the plants have been labeled according to the following features: (o) plants already equipped with efficient polishing (or tertiary) sections; (x) plants whose polishing sections are under construction; (#) plants that need to be structurally upgraded and/or equipped with infrastruc-
168
A. Lopez, M. Vurro / Desalination 218 (2008) 164–169
Table 2 Apulia Region: municipal facilities potentially exploitable for reusing their treated wastewater Municipality
Plant features
Alberobello Andria Avetrana Bari Est Bari Ovest Barletta Carpignano Sal. Casarano Castellana Grotte Castellaneta Cerignola Conversano Corsano Fasano Forc. Foggia Gallipoli Lecce Lizzano Lucera Maglie Margherita di Sav. Maruggio Massafra Mesagne Ostuni Ruvo-Molfetta S. Ferdinando di P. San Severo Sternatia Taranto Bellavista Taranto Gennarini Torchiarolo Trinitapoli Vieste Total
# x, #, ^ x, #, ^ o x x, #, ^ x o, #, ^ x, #, ^ # x, #, ^ o x o, #, ^ # x, #, ^ o, #, ^ o #, ^ #, ^ o, #, ^ o, #, ^ o o, #, ^ o x, #, ^ # x, #, ^ # o, #, ^ o o # x
tural works; (^) plants whose funding of the necessary upgrading is already secured by regional, national and/or European sources. During the first phase of the regional master plan implementation, about 50% of the total recoverable volumes in Table 2 will be actually reused. From the technological point of view most of
Plant capacity (m3/d) 1,900 13,000 1,700 78,000 13,000 17,000 2,500 3,500 1,300 3,600 8,000 6,000 2,500 3,500 30,000 17,300 20,000 3,300 4,400 12,000 3,000 2,700 8,000 14,000 5,500 25,000 3,000 7,000 850 50,000 77,000 800 3,500 3,320 446,170
Recoverable volumes (m3/y) 340,000 2,600,000 310,000 6,000,000 3,900,000 3,400,000 450,000 630,000 250,000 648,000 1,450,000 1,200,000 450,000 700,000 5,500,000 3,200,000 3,600,000 600,000 792,000 3,600,000 540,000 500,000 1,400,000 2,500,000 1,100,000 4,500,000 540,000 1,260,000 150,000 15,000,000 23,100,000 160,000 630,000 560,000 91,560,000
the plants in Table 2 have been designed or are running according to the treatment-train presented in Fig. 6, where the prevalent options are ferric chloride (as coagulant), anionic polyelectrolyte (as coadjutant of flocculation), sand + anthracite or sand (as filtration media), chlorine or UV (as disinfectants). This scheme, technologically known as “full treatment”, although rather conventional is
A. Lopez, M. Vurro / Desalination 218 (2008) 164–169
II effluent
Equalization
Coagulation
Flocculation
Reuse
Disinfection
Filtration
Sedimentation
169
Fig. 6. Treatment train designed for most of the Apulian MWWTPs whose effluents will be reused in agriculture.
very effective [10]. In fact, although characterized by a certain degree of complexity such a scheme presents very few performance risks. 3. Conclusions In the sector of water resources management, agricultural wastewater reuse can effectively contribute to fill the increasing gap between water demand and water availability particularly in semi-arid areas such as the Apulia region. After a period featured by a few initiatives for increasing the availability of the local water resources and by the lack of clear regulations, under the pressure of several factors (i.e., frequent drought periods, progressive worsening of local groundwater quality, growth of agricultural activities, need of implementing new regulations) the regional authorities have finally planned, at regional scale, the reuse of treated wastewater mainly in the agricultural sector. In the coming years, then, Apulia region will represent, at National as well as European scale, a regional-scale laboratory where proving both the validity of such a strategic choice for implementing local water resources availability and the effectiveness of the adopted technical solutions. References [1]
Decreto del Commissario Delegato Emergenza Ambientale 19/12/2005, n. 209, Definizione e Predisposizione, ai sensi del combinato disposto degli artt. 2, comma 1, e 7, comma 3, Ordinanza 22 Marzo 2002, n.3184 Ministero dell’Interno delegato per il coordinamento della protezione civile, del “Piano di tutela
delle Acque” di cui all’art.44 D.Lgs. n. 152/99, BURP n. 6 12/1/2006. [2] IRSA-CNR, Un futuro per l’acqua in Italia, Quaderno, 109 (1999). [3] AQP web-site. http://www.aqp.it/home.htm [4] I. Portoghese, V. Uricchio and M. Vurro, A GIS tool for hydrogeological water balance evaluation on a regional scale in semi-arid environments. Computers Geosci., 31(1) (2005) 15–27. [5] M. Maggiore, G. Raspa, L. Sabatelli, D. Santoro, O. Santoro and M. Vurro, Monitoring of seawater intrusion in a karst aquifer (Apulia, southern Italy). Proc. First International Conference on Saltwater Intrusion and Coastal Aquifers — Monitoring, Modeling, and Management. Essaouira, Morocco, April 23–25, 2001. [6] Ministero dell’Ambiente e della Tutela del Territorio, D.Lgs n.152/99: Disposizioni sulla tutela delle acque dall’inquinamento e recepimento della direttiva 91/271/ CEE concernente il trattamento delle acque reflue urbane e della direttiva 91/676/CEE relativa alla protezione delle acque dall’inquinamento provocato dai nitrati provenienti da fonti agricole. Gazzetta Ufficiale N.172/L, 20 Ottobre 2000. [7] Ministero dell’Ambiente e della Tutela del Territorio, D.Lgs n. 185/03: Regolamento recante norme tecniche per il riutilizzo delle acque reflue in attuazione dell’articolo 26, comma 2, del decreto legislativo 11 maggio 1999, n.152. Gazzetta Ufficiale N. 169, 23 Luglio 2003. [8] Sogesid S.p.A. Regione Puglia: Piano direttore a stralcio del piano di tutela delle acque, Relazione Generale, 2002. [9] Regione Puglia, Piano d’Ambito approvato dal Commissario delegato per l’emergenza ambientale con Decreto n° 294 del 30.9.2002, in applicazione dell’art. 11 della Legge n. 36/94 (2002). [10] V. Lazarova, Drivers and constraints for water reuse development in Europe, Proc. Seminar and Symposium on Wastewater Reclamation and Reuse, LIFE 99/ENG/ GR/000590, Thessaloniki, Greece, 13–14 February 2003, pp. 65–78.
Planning agricultural wastewater reuse in southern Italy: The case of Apulia Region A. Lopez*, M. Vurro Consiglio Nazionale delle Ricerche, Istituto di Ricerca Sulle Acque, Via F. De Blasio 5, 70123 Bari, Italy Tel. +39 (080) 5820511; Fax +39 (080) 5313365; email: [email protected], [email protected]
Received 1 February 2006; accepted 30 August 2006
Abstract The future of southern Italian regions lays mainly on conservation and recovery of their peculiar environment (i.e., pleasant climate, beautiful nature and historic heritage). Presently, most of such regions have to face major problems related to water shortage for agriculture and, in some cases, even for drinking purposes. In these regions water shortage is a growing problem and wastewater reclamation and reuse, a key options for their sustainable development, has not yet been implemented at large scale. In these regions, the interest for wastewater reuse is particularly addressed to agricultural and landscape irrigation with the aim of both enhancing the local economy, mostly based on agriculture, and saving good quality water resources for drinking purposes. Referring to the Apulia region, it has many analogies with other areas affected by chronic water scarcity, i.e: the rapid development of local economy, the changes in traditional agriculture practices and land use, the groundwater over-exploitation with consequent sea water intrusion, the climate changes. The mix of all these factors, although with a different weight, has been the main cause of the frequent water shortage problems recorded in the region. Although over the last decades these problems have been partially mitigated by the construction of water transport infrastructures and reservoirs, they are still far to be definitely solved. Because of this, finally, regional authorities have defined a water resources protection and management master plan in which the reuse of treated wastewater, not only in agriculture, plays a relevant role [1]. This paper outlines the local environmental conditions and the rationale supporting such a choice. Keywords: Agricultural wastewater reuse; Wastewater treatment; Water resources management
*Corresponding author.
Presented at AQUAREC 2006 — Integrated Concepts for Reuse of Upgraded Wastewater, Barcelona, 1–3 February 2006 0011-9164/08/$– See front matter © 2008 Published by Elsevier B.V. doi:10.1016/j.desal.2006.08.027
A. Lopez, M. Vurro / Desalination 218 (2008) 164–169
1. Introduction In Italy, an overall annual water inflow around 155 billions m3 yields only 52 billions m3 of resources actually utilizable. Because of the geographically uneven rainfalls distribution, in southern regions (e.g., Apulia, Sicily and Sardinia) such figures drastically decrease as rainfalls result much lower than the national average (980 mm/y) [2]. Furthermore, in such regions, only part (15– 20%) of these scarce water resources is actually available mainly because of their out of date water distribution systems. At national level, Apulia, a southern-eastern region extended for about 20,000 km2 with 800 km of coasts and 4,500,000 inhabitants, owns the smallest amount (136 m3/capita/y) of potentially available water resources [2]. Nevertheless, the economy of the region, mainly based on two water demanding activities, agriculture and tourism, is ranked as one of the best in the south. This is possible thanks to the Apulian water agency (AQP) that imports water from bordering regions such as Campania, Lucania and Molise. AQP manages the largest European aqueduct, a complex multi-purposes and multi-reservoirs system with 19,635 km of distribution networks. It serves 4,623,349 inhabitants and distributes, net of leakages, 309,416,113 m3 of drinking water [3]. As for the agricultural sector, although it is served by large irrigation-water distribution consortia, a negative gap of about 700 Mm3 exists. To fill this gap, it has been estimated that regional farmers have drilled, more or less legally, about 140,000 wells whose extensive exploitation has caused the progressive salinization and depletion of relevant portions of the local aquifers. In order to manage such a situation, regional authorities in addition to drastically restrict water wells drilling have also planned a strategic reuse, in agriculture as well as in industry, of treated municipal wastewater (MWW) [1]. Referring only to the agricultural sector, this paper is aimed at qualitatively describing some features of the Apulia region related to its water
165
resources scarcity, the criteria that have driven the selection of the MWW treatment plants whose effluents have been planned to be reused in agriculture and some information concerning the treatment-scheme of such plants. 2. Planning agricultural wastewater reuse in Apulia 2.1. Environmental drivers As shown in Fig. 1, Apulia is the Italian region with the lowest rainfall average value (i.e. about 660 mm) [2]. Furthermore because of its orography and its hydro- geological subsoil features, its average runoff coefficient value (0.23) is also the lowest. This value has been calculated, by a model designed for evaluating groundwater recharge through a soil-water balance, taking into account inflows (rainfall, irrigation) and outflows (plant evapotranspiration, surface run-off) [4].
<500 501-750 751-1000 1001-1500 1501-2000 2001-2500 >2500
APULIA
Fig. 1. Rainfalls distribution in Italy: average values (mm) in the period 1950–2000.
166
A. Lopez, M. Vurro / Desalination 218 (2008) 164–169
In spite of the scarce regional rainfalls, Fig. 2 shows that most (78.8%) of the Apulian land is used for agricultural purposes (i.e., 15,239 km2 over a total area of 19,332 km2). In must be noted, however, that only 23.8% (i.e., 3,653 km2) of the cultivated area is irrigated. Notwithstanding such a small portion of irrigated land, in order to satisfy the agricultural water demand, as shown in Fig. 3, in the region, relevant amounts of water are withdrawn from local aquifers [4].
Of course, because of such a groundwater overexploitation, particularly in coastal areas, a sharp salinity increase, with peaks such high as 20,000 µS/cm, has taken place due to sea water intrusion phenomena (Fig. 4) [5]. 2.2. Legislative framework From the legislative standpoint the above mentioned regional master plan is based mainly on two national laws, i.e. the D.Lgs n.152/99 and n. 185/03 [6,7]. The latter law, for the fist time, clearly fixed the qualitative standards for WW agricultural reuse (Table 1) giving to each region, if justified, the possibility to modify only some parameters. As for D.Lgs n.152/99, it combines the European Directives 91/271/EEC (on the treatment of urban wastewater) and 91/676/EEC (on water resources protection from the pollution caused by nitrates from agricultural sources). Moreover, this law provides general provisions for protecting water resources from whatever pollution. Among such provisions, one imposes that wastewater discharge into subsoil, a rather frequent practice in Apulia, has to be stopped as soon as possible, in-
Fig. 2. Land use in Apulia.
0 0000008 4 1 2 8 9 5 4 4 4 3 3 2 3 )0 m 0 04 01 02 08 05 9 52 m2 4 34 33 ( N O I T A 00005 0 G 03 6 9 2 I 01 0 1 1 1 2 2 R 05 R1 -I 03 06 09 02 0 -0 L 00 A U 01511112 N N A
KEY
Fig. 3. Groundwater withdrawals (mm/y) for irrigation purposes in Apulia.
Fig. 4. Electrical conductivity (µS/cm) of Apulian aquifers.
A. Lopez, M. Vurro / Desalination 218 (2008) 164–169
167
Table 1 Main quality parameters fixed by the Italian law (D.Lgs n. 185/03) for agricultural reuse of municipal wastewater
Parameter
Value
pH Coarse solids, mg/L TSS, mg/L COD, mg/L BOD5, mg/L Boron, mg/L Chlorides, mg/L Sulphates, mg/L Electrical conductivity, µS/cm Total phosphorus, mg/L Total nitrogen, mg/L Grease and oil, mg/L Aldehydes, mg/L Surfactants Chlorinated pesticides Escherichia coli, CFU/100 ml Salmonella, CFU/100 ml Sodium adsorption ratio
6–9.5 absent 10 100* (50) 20* (10) 1.0* (2.0) 250* (500) 500 3,000 10 35 10 0.5 0.5 0.0001 10 absent 10
(*) Values modified by the Apulia region with those in parenthesis.
dicating the reuse of treated wastewater as a feasible alternative. Such provisions together with the persistent water resources scarcity have finally convinced the regional Government to insert the reuse of municipal wastewater in the official planning of the management of regional water resources [1]. 2.3. Wastewater availability and technical issues In the whole region there are 215 wastewater treatments plants: 173 managed by AQP, 29 by single municipalities, 2 directly by the Apulia region and 11 not yet in operation. The plants managed by AQP (Fig. 5) have a total designed capacity of about 250 Mm3/y of treated WW [8,9]. The regional master plan that defines the whole strategy for the protection and the management of local water resources also provides the details
Fig. 5. Distribution of the municipal wastewater treatment plants managed by the Apulian Water Agency (AQP).
(i.e., MWWTPs exploitable, available WW volumes, costs, timing, etc.) for implementing the programmed wastewater reuse [1]. In particular, it takes into account that from the technological, infrastructural, logistic and economic standpoints, not all the AQP plants can be involved in the wastewater reuse plan. In fact, some of them have a small capacity, or are very far from agricultural districts, or are equipped only with preliminary or primary treatment sections, or cannot be connected to the necessary infrastructural-works (e.g., wastewater distribution pipelines, etc.). All such plants features have been inserted in a GIS tool that has been used for identifying, in a first planning-step, those plants (Table 2) potentially utilizable, in relatively short time, for reusing their treated wastewater (it must be pointed out that the recoverable volumes reported in Table 2 are only those planned to be reused in the reference area). In Table 2 the plants have been labeled according to the following features: (o) plants already equipped with efficient polishing (or tertiary) sections; (x) plants whose polishing sections are under construction; (#) plants that need to be structurally upgraded and/or equipped with infrastruc-
168
A. Lopez, M. Vurro / Desalination 218 (2008) 164–169
Table 2 Apulia Region: municipal facilities potentially exploitable for reusing their treated wastewater Municipality
Plant features
Alberobello Andria Avetrana Bari Est Bari Ovest Barletta Carpignano Sal. Casarano Castellana Grotte Castellaneta Cerignola Conversano Corsano Fasano Forc. Foggia Gallipoli Lecce Lizzano Lucera Maglie Margherita di Sav. Maruggio Massafra Mesagne Ostuni Ruvo-Molfetta S. Ferdinando di P. San Severo Sternatia Taranto Bellavista Taranto Gennarini Torchiarolo Trinitapoli Vieste Total
# x, #, ^ x, #, ^ o x x, #, ^ x o, #, ^ x, #, ^ # x, #, ^ o x o, #, ^ # x, #, ^ o, #, ^ o #, ^ #, ^ o, #, ^ o, #, ^ o o, #, ^ o x, #, ^ # x, #, ^ # o, #, ^ o o # x
tural works; (^) plants whose funding of the necessary upgrading is already secured by regional, national and/or European sources. During the first phase of the regional master plan implementation, about 50% of the total recoverable volumes in Table 2 will be actually reused. From the technological point of view most of
Plant capacity (m3/d) 1,900 13,000 1,700 78,000 13,000 17,000 2,500 3,500 1,300 3,600 8,000 6,000 2,500 3,500 30,000 17,300 20,000 3,300 4,400 12,000 3,000 2,700 8,000 14,000 5,500 25,000 3,000 7,000 850 50,000 77,000 800 3,500 3,320 446,170
Recoverable volumes (m3/y) 340,000 2,600,000 310,000 6,000,000 3,900,000 3,400,000 450,000 630,000 250,000 648,000 1,450,000 1,200,000 450,000 700,000 5,500,000 3,200,000 3,600,000 600,000 792,000 3,600,000 540,000 500,000 1,400,000 2,500,000 1,100,000 4,500,000 540,000 1,260,000 150,000 15,000,000 23,100,000 160,000 630,000 560,000 91,560,000
the plants in Table 2 have been designed or are running according to the treatment-train presented in Fig. 6, where the prevalent options are ferric chloride (as coagulant), anionic polyelectrolyte (as coadjutant of flocculation), sand + anthracite or sand (as filtration media), chlorine or UV (as disinfectants). This scheme, technologically known as “full treatment”, although rather conventional is
A. Lopez, M. Vurro / Desalination 218 (2008) 164–169
II effluent
Equalization
Coagulation
Flocculation
Reuse
Disinfection
Filtration
Sedimentation
169
Fig. 6. Treatment train designed for most of the Apulian MWWTPs whose effluents will be reused in agriculture.
very effective [10]. In fact, although characterized by a certain degree of complexity such a scheme presents very few performance risks. 3. Conclusions In the sector of water resources management, agricultural wastewater reuse can effectively contribute to fill the increasing gap between water demand and water availability particularly in semi-arid areas such as the Apulia region. After a period featured by a few initiatives for increasing the availability of the local water resources and by the lack of clear regulations, under the pressure of several factors (i.e., frequent drought periods, progressive worsening of local groundwater quality, growth of agricultural activities, need of implementing new regulations) the regional authorities have finally planned, at regional scale, the reuse of treated wastewater mainly in the agricultural sector. In the coming years, then, Apulia region will represent, at National as well as European scale, a regional-scale laboratory where proving both the validity of such a strategic choice for implementing local water resources availability and the effectiveness of the adopted technical solutions. References [1]
Decreto del Commissario Delegato Emergenza Ambientale 19/12/2005, n. 209, Definizione e Predisposizione, ai sensi del combinato disposto degli artt. 2, comma 1, e 7, comma 3, Ordinanza 22 Marzo 2002, n.3184 Ministero dell’Interno delegato per il coordinamento della protezione civile, del “Piano di tutela
delle Acque” di cui all’art.44 D.Lgs. n. 152/99, BURP n. 6 12/1/2006. [2] IRSA-CNR, Un futuro per l’acqua in Italia, Quaderno, 109 (1999). [3] AQP web-site. http://www.aqp.it/home.htm [4] I. Portoghese, V. Uricchio and M. Vurro, A GIS tool for hydrogeological water balance evaluation on a regional scale in semi-arid environments. Computers Geosci., 31(1) (2005) 15–27. [5] M. Maggiore, G. Raspa, L. Sabatelli, D. Santoro, O. Santoro and M. Vurro, Monitoring of seawater intrusion in a karst aquifer (Apulia, southern Italy). Proc. First International Conference on Saltwater Intrusion and Coastal Aquifers — Monitoring, Modeling, and Management. Essaouira, Morocco, April 23–25, 2001. [6] Ministero dell’Ambiente e della Tutela del Territorio, D.Lgs n.152/99: Disposizioni sulla tutela delle acque dall’inquinamento e recepimento della direttiva 91/271/ CEE concernente il trattamento delle acque reflue urbane e della direttiva 91/676/CEE relativa alla protezione delle acque dall’inquinamento provocato dai nitrati provenienti da fonti agricole. Gazzetta Ufficiale N.172/L, 20 Ottobre 2000. [7] Ministero dell’Ambiente e della Tutela del Territorio, D.Lgs n. 185/03: Regolamento recante norme tecniche per il riutilizzo delle acque reflue in attuazione dell’articolo 26, comma 2, del decreto legislativo 11 maggio 1999, n.152. Gazzetta Ufficiale N. 169, 23 Luglio 2003. [8] Sogesid S.p.A. Regione Puglia: Piano direttore a stralcio del piano di tutela delle acque, Relazione Generale, 2002. [9] Regione Puglia, Piano d’Ambito approvato dal Commissario delegato per l’emergenza ambientale con Decreto n° 294 del 30.9.2002, in applicazione dell’art. 11 della Legge n. 36/94 (2002). [10] V. Lazarova, Drivers and constraints for water reuse development in Europe, Proc. Seminar and Symposium on Wastewater Reclamation and Reuse, LIFE 99/ENG/ GR/000590, Thessaloniki, Greece, 13–14 February 2003, pp. 65–78.